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Airflow problem in the basement

My family and I moved into our new home 3 months ago. Turned on the heat and the end of October and my wife who stays home with our toddler age kids noticed the stuffy air in the basement. I reached up with my hand against registers and the airflow is really low - probably less than half of what it feels like on the main level.

We had a heating tune-up, seasonal checkup done yesterday and were told the furnace runs well - no issues. The filters are clean.

We also had a contractor today who inspected the ducts - the main supply duct and the return down in the utility room. He said that he could not see any dampers on the main supply duct (that goes up from the furnace leading up to the main level and branches off horizontally to the basement). He also said that he thought there may be registers that have been sealed off inside the drywalls; or some other problem that's restricting airflow velocity. He did not perform additional in-depth testing.

This is a Winchester Homes colonial type SFH built in 1999. The basement was finished by the previous owner after they initially bought the house.

Is there a cost-effective way to repair this problem without opening up drywalls to locate a potential area of air leakage or airflow being restricted?
Do you know of any specific tests or equipment that can be used/installed to troubleshoot this problem?

You say you reached UP to feel the supply registers in the basement. That is the first problem - heated air delivered high in the room will NOT go down from there. The floors will not be warmed that way.

At first reading it seemed this was a new house, but you later write that the house was built in 1999.
If the previous owner is the one who finished the basement and installed the supply runs then he probably did it poorly.
As for a "cost effective" way to repair it, the only way to repair it is to thoroughly inspect what is there to determine if it can be rectified. You may be better off abandoning the basement supply runs and having a knowledgeable heating contractor do it right.

My experience hiring AC/Heating service companies so far has been for things such as ac/heating seasonal tune-ups.

Do I need to get a qualified HVAC service company that specializes in the duct rework? What/how do I screen out through through local companies and select the one for this type of job to make sure time and efforts don't go wasted and I get an honest trustworthy analysis of the problem?

Can you pls educate me on the following:

- Questions to ask
- Equipment can be used to troubleshoot this problem
- Technical tests a contractor should run as part of the analysis

My experience hiring AC/Heating service companies so far has been for things such as ac/heating seasonal tune-ups.

Do I need to get a qualified HVAC service company that specializes in the duct rework? What/how do I screen out through through local companies and select the one for this type of job to make sure time and efforts don't go wasted and I get an honest trustworthy analysis of the problem?

Can you pls educate me on the following:

- Questions to ask
- Equipment can be used to troubleshoot this problem
- Technical tests a contractor should run as part of the analysis

Thanks!

First, no offense to Dean, you can heat a basement (if done properly) with ceiling registers.

In my 30+ years, I have found that you'll have a hard time finding someone that wants to jack with your problem. Either they don't care (think there is any money to be made) or they don't know dilly.

I do not understand your thread. You said no air is coming out of the basement registers, then you said a contractor thought supplies are covered by the sheetrock. Which is it?

Can you see the main ductwork (rectangle shaped)? The supplies (that branch off) will be round. If there are no dampers (a pet peeve of mine) in the supplies, then it'll be hard to redirect the airfow.

If one is able to get to each supply, zoning may be possible. Sweet! You then can have a thermostat on each floor. I have 3 in my home.

Ok, here are some more details. I've got two gas furnaces. The first one located in the utility room in the basement (Rheem 75000 BTU/hr), and the second gas furnace is in the attic (also Rheem 50000 BTU/hr). The first furnace supplies air to the basement and the main level, the second one is dedicated to the upper level. Two thermostats - one on the main level and one upstairs.

Now as far as the air.. The air velocity is fine on the main level. The problem is that air velocity coming out of ceiling registers in the basement is low. I can feel the air and the warmth when I put my hand against the grills, but the air speed/velocity seems weak.

I can see the main supply duct. It comes up vertically from the furnace (above the heat exchanger) and goes up through the floor to the main level. That's that.

Now, this main duct also has a branch that splits off the main duct and goes horizontally along the ceiling parallel to the floor in the utility room and then it looks like it becomes invisible because at the point it becomes enclosed inside the drywall which is at the point where the utility room ends.

Your Specific issue (... stuffy) is Not Simple to address without discovering the exact air flow distribution and relative humidity in varying conditions.
It is your choice whether you may need " an air doctor".

Ok, here are some more details. I've got two gas furnaces. The first one located in the utility room in the basement (Rheem 75000 BTU/hr), and the second gas furnace is in the attic (also Rheem 50000 BTU/hr). The first furnace supplies air to the basement and the main level, the second one is dedicated to the upper level. Two thermostats - one on the main level and one upstairs.

Now as far as the air.. The air velocity is fine on the main level. The problem is that air velocity coming out of ceiling registers in the basement is low. I can feel the air and the warmth when I put my hand against the grills, but the air speed/velocity seems weak.

I can see the main supply duct. It comes up vertically from the furnace (above the heat exchanger) and goes up through the floor to the main level. That's that.

Now, this main duct also has a branch that splits off the main duct and goes horizontally along the ceiling parallel to the floor in the utility room and then it looks like it becomes invisible because at the point it becomes enclosed inside the drywall which is at the point where the utility room ends.

I've got a picture in my head (Ted is right, pictures would be great). You maybe real lucky.
Until I "see" what I'm envisioning (sp?) I won't confuss you with my "thoughts".

I do hope that someone hasn't tapped off the first floor supplies. Stick your hand into a basement supply (it helps to take off the register ). It should only go one way.

I agree with George2 that it is possible to heat the basement with registers high in the room "if done properly." But there's the catch - to do it properly will require some returns low in the room, but the floor will be warmer if the supply runs are low. From the sound of things this will not be a "cheap" thing to fix. There will be some labor (and knowledge) involved.

As for your pictures, they don't show any of the supply ducts or the "registers that have been sealed off inside the drywalls (sic)."